CARGO-STEERING-CONNECTION_report

  1. Study Overview
  2. Simulation Setup
    - Geometry
    - Materials
    - Boundary Conditions
    - Loading
    - Mesh
  3. Simulation Steps
  4. Results
    - Stress Analysis
    - Displacement Analysis
    - Other Results
  5. Conclusions
  6. Appendix
    - Mesh Details
    - Material Properties
    - References

🎯 Study Overview

Goal of the Study:

The goal is to evaluate on a simple model if the interface for steering integrated in the crown is robust enough considering the assembly and interaction with the other components. Ths evaluation, with very high safety margin should indicate if any aeras are submitted to high stress concentration so we could reinforce the initial 3D model

Key Parameters:

Expected Outcomes:

🔧 Simulation Setup

Geometry

Geometry is one of a crown with an added extrusion that allow the fixation of a connecting hardware for remote steering often seen on cargo bike. This avoid to clamp on stanchions and allow for full travel of the fork

model_raw.png

Materials

Property Value Unit
Name Aluminum 6061 -
Density 2.71 g/cc
Young Modulus 69000 MPa
Poisson Ratio 0.33

Boundary Conditions

Loading

We apply a loading force on the reference point at the pin hole that gets transmitted to the holes surface through a rigid surface constraint

Mesh

model_setup.png

Mesh Statistics:

📊 Simulation Steps

Step number / title 1 - STATIC Positive loading
Iterations for convergence 1
Convergence criteria -
Notes +1500N
Step number / title 2 - STATIC Negative loading
Iterations for convergence 1
Convergence criteria -
Notes -1500N

📈 Results

Stress Analysis

Von Mises Stress

STATIC_LOADING_VM_1500N.png

Maximum Von Mises Stress: 60.89 MPa
Stresses observed are well below any critical value that would lead to plastic deformation that usually start around 280MPa for this type of Aluminium

Displacement Analysis

For a force applied of 1500N (different to the one showed in picture before), we observe a 6.626mm displacement max
For a force applied of 2500N (different to the one showed in picture before), we observe a 11mm displacement max

🔍 Conclusions

Both directions (the one of travel and the opposite of travel) were simulated with very similar results which was expected given the quasi-symmetrical geometry.

The loading values 1500N and 2500N have a very high safety factor that would only occur in brutal circumstances like a crash. They are likely overvalued as the steering rod will likely bend or slide at the interface with the steering tube before we reach such values on the crown.

The stress values are well within the elastic domain of the crown material so the current design does not show any critical area that would need revision. Also, we do not think refining the mesh on the current setup will significantly improve the results, so the confidence is high for a first evaluation.

Key Findings:

Recommendations: